Another class of related models are models for the virtual machine (VM) scheduling problem [1]}, [2]}, [3]}, [4]}, [5]}, but again only limited results are available for job response times and most works focus on stability. In the VM scheduling problem, a VM job requests multiple units of resource such as CPUs. But the server model in VM scheduling is different from the multi-server job model we study in this paper. In VM scheduling, a server has several CPUs and usually can accommodate multiple jobs, but a job cannot be spread across multiple servers.
